Developing a electronic fuel sending unit fix?

[dpok69]

My digital dash fuel level is 3 gallons out of spec. Without pulling out the tank and actually messing with the sender i was thinking if I can make a device that interupts the fuel level signal and modifies it so we can tweak our fuel level to the right positions.

The fuel level works by resistance reading if i understand correctly. So i were to put a potentiometer resistor in series with the original signal i can increase resistance levels and fool the dash.

But if i want to decrease the resistance readings, then i would have to make a circuit parallel to the sender, which would most likely result in pulling down the tank anyway. Still a good idea for people who cannot tweak there senders to work correctly.

I wonder if there is another way to decrease resistance by using a series ckt so the gas tank does not have to be pulled out. if there is, we can have two potentiomers one for increasing and one for decreasing resistance. In this way we can tweak our displays to read the actual level of gasl.

Any ideas , suggestions?

 

[WarpSpeed]

Alot of times the problem with the fuel gauge is behind the dash cluster where the fuel gauge wiring plugs into the dash. It's similiar to a 110ac plug and can/does corrode and effect the readings.

 

[TurboRegal84]

For the Digital dash cars if you just "Key On" the car (Car not running, just ign on) it should display the accurate amount of fuel.

With my car I know when it gets down to 8 gal's with the car running it is around 4 gals with the key switched on.


I remember a thread on here a while back that stated the senders are accurate when the charging system is not charging (key on), but once you start the car, and get the alt. moving it somehow messes up the reading on your dash.

Hope this provides you with some helpful insight.

 

[dpok69]

I have noticed while the car sits with the key in the guage reads a lower level then when the car starts up. But i thought this was normal since most cars do this.